The priority application Number Japanese Patent Application 2004-075767 upon which this patent application is based is hereby incorporated by reference.
1. Field of the Invention
This invention relates to a circular connector assembly, of which male and female connectors are electrically connected to each other via an engaging ring for use in, for example, a transmission of a vehicle.
2. Description of the Related Art
As shown in FIGS. 8 and 9, Japanese published unexamined patent applications No. Hei 04-132178 (pages 4 to 6, FIG. 1) and Hei 10-154553 (page 3 to 5, FIG. 1) disclose first and second embodiments of conventional circular connector assemblies 70 in FIG. 8, 80 in FIG. 9. The circular connector assembly 70 is a multipin connector assembly accommodating a plurality of terminals 72, 74. A male and female connectors 71, 73 of the circular assembly 70 are connected to each other by rotating an engaging ring 76. Generally, force for connecting the male and female connectors increases as a number of terminals increases. However, the connectors 71, 73 of the circular connector assembly 70 are easily connected to each other by rotating the engaging ring 76 with a small force without prying the terminals 72, 74.
As shown in FIG. 8, the conventional circular connector assembly 70 includes a male connector 71 having female terminals 72; a female connector 73 having male terminals 74, and a helical groove 75 on an outer surface thereof, and being connected to the male terminal 71; and an engaging ring 76 mounted rotatably on the male connector 71, and having projections 77 for engaging with the helical groove 75. Thereby, after the projections 77 are engaged with the helical groove 75, rotating the engaging ring 76 makes the male and female connectors 71, 73 connected to each other. When the male and female connectors 71, 73 are connected to each other, the male and female terminals 74, 72 are electrically connected to each other.
As shown in FIG. 9, the conventional circular connector assembly 81 allows to recognize a fitting condition of the male 81 and female (not shown) connectors. This assembly 80 includes the male 81 and female connectors; an engaging ring 85 mounted rotatably on the male connector 81 to connect the male 81 and female connectors; and a detector 86 mounted on a receiving part 82a as a concave formed on an outer periphery of a flange 82 of the male connector 81 to indicate the fitting condition of the male 81 and female connectors.
A circular guiding rail 83 is provided on an outer surface of the male connector 81. A guiding part (not shown) provided on an inner surface of the engaging ring 85 engages with the guiding rail 83, and thereby the engaging ring 85 is rotatably mounted on the male connector 81. The detector 86 is mounted, slidably in an axis direction of the circular connector assembly, on the receiving part 82a of the flange 82.
The female connector (not shown) includes a hood (not shown) for receiving the male connector 81. A helical groove (not shown) is formed on an outer surface of the hood. When a projection (not shown) formed on the inner surface of the engaging ring 85 is engaged with the helical groove, and the engaging ring 85 is rotated in a counterclockwise direction, the male 81 and female connectors approach each other in the axis direction of the assembly 80 to be connected to each other.
The detector 86 includes an engaging projection 86a, which projects toward the engaging ring 85 for detecting an engagement between the connectors. This engaging projection 86a engages with an engaging concave 85a formed at a front end of the engaging ring 85. An engaging concave 85a is formed on a periphery of the engaging ring 85 at a reference position for assembling. Only when the engaging concave 85a faces the engaging concave 85a, the engaging convex 86a of the detector 86 is engaged with the engaging concave 85a. This circular connector assembly is designed that when the detector faces the engaging concave 85a, the male 81 and female connectors are fully engaged with each other. Otherwise, the engaging convex 86a is not engaged with the engaging concave 85a, and the detector 86 is projected from an end surface of the flange 82. Namely, the fitting state of the male 81 and female connectors is detected by whether the engaging projection 86a of the detector 86 is engaged with the engaging concave 85a of the engaging ring, or not.
As a third embodiment, Japanese published unexamined patent application No. 2001-6814 (page 3) discloses a conventional circular connector assembly (not shown). Male and female connectors of the assembly are pressed in an axial direction of the assembly to be connected to each other. An engaging ring is rotated to disconnect the male and female connectors.
However, there are problems as described below in the conventional circular connector assemblies. Regarding the first embodiment as the circular connector assembly 70 shown in FIG. 8, whether the connectors 71, 73 are fully connected to each other or not is only detected by a torque feeling (operator's judgement that the engaging ring could not rotate further). Therefore, sometimes a half-fitting condition of the connectors 71, 73 is mistaken for a fully fitting condition. Thus, reliability of the circular connector assembly 70 is not high.
Regarding the second embodiment as the circular connector assembly 80 in FIG. 9, there is a problem that a number of components of the assembly 80 to be managed is increased, and a management of the components of the assembly 80 is troublesome. Further, a number of operation steps for connecting the connectors is increased by one, since the detector 86 is pressed into the engaging ring 85 for detecting the fitting condition of the connectors after connecting the connectors.
Regarding the third embodiment of the circular connector assembly, there is a problem similar to the first embodiment that the fitting condition of the male and female connectors of the assembly is not detected surely, and sometimes a half-fitting condition of the connectors is mistaken for a fully fitting condition.
Accordingly, it is an object of this invention to provide a circular connector assembly that allows to improve fitting reliability of male and female connectors without increasing a number of components of the assembly, and to improve maintenance workability of the assembly due to connecting and disconnecting the male and female connectors easily, and adapts to miniaturization of such as an engine room.